Go Modules Dockerfile

Dockerfile

FROM golang:1.12 AS build
COPY go.mod go.sum m/
RUN cd m && go mod download
COPY . srcroot
RUN cd srcroot && go install -mod=readonly ./cmd/foo \
  && go clean -modcache -cache std

FROM debian:stretch-slim
RUN apt-get update && apt-get install -y --no-install-recommends \
    ca-certificates \
  && rm -rf /var/lib/apt/lists/*
COPY --from=build /go/bin/foo /usr/bin/foo
ENTRYPOINT ["/usr/bin/foo"]